Stop-valve.



J. DEWRANCE.

STOP VALVE.

APPLICATION FILED APR. 18, I914.

Patented Apr. 27, 1915.

fay- MINE-$855:

' To all whom it may concern UNITED s'ra'rns arana UFFICE.

Jonnnnwanncn, on SOUTHWARK, ENGLAND STOP-VALV E.

Specification of Letters Patent.

Application filed April 18, 1914. Serial No. 832,945.

Be it known that I, JOHN DEWRANOE, a subject of the King of Great Britain and Ireland, residing at 165 Great Dover street, Southwark, in the county of Surrey, England, have invented new and useful Improvements in Stop-Valves, of which the following is a specification. v

This invention relates to stop-valves of the sliding gate type, such as commonly employed for controlling steam passages and water ways of considerable size and wherein the gate or shutter partakes of a sliding movement between parallel seatings arranged on either side thereof.

In stop-valves of the kind above referred to, the shutter commonly comprises two disks between which is arranged a spiral or other spring which serves to maintain the opposite faces of the valve in close contact with the seatings which respectively terminate the inlet and outlet passages formed in the valve-casing when the valve is opened and the greater portion of the shutter is withdrawn from between the said seatings, it is necessary to prevent the two disks separating under the influence of the intervening springs; and my present invention relates to improved means for accomplishing this object, as also for facilitating the assemblage of the parts, and to afford increased safety during dismounting, the valve being securely attached to the spindle whereby it is operated.

In the accompanying drawings is represented a stop-valve constructed according to my improved method; Figure 1 being a transverse section, Fig. 2 a longitudinal section and Fig. 3 a sectional plan view on the line 00-01? in Fig. 1. Fig. 2 shows on an enlarged scale the valve facing embodied in Fig. 2.

The shutter comprises two disks A A having between them a spiral spring B. In the periphery of each of the disks is formed a groove a, and concentrically with the disks is arranged a ring C, the lower portion of which is formed with two snugs c which project radially inward; these snugs being adapted to engage in the circular grooves a, a, formed in the two disks A A. The lower extremity of the hollow spindle 1) whereby the shutter is raised and lowered, is similarly provided with two snugs d cl adapted to engage in the upper portions of the circular grooves a a formed in the two disks. The ring C is formed with a head 0 beneath which is inserted horizontally a U- shaped keep E; thelatter engaging with the hollow spindle D by means of two lateral recesses or flats cl d formed for its reception. The U-shaped keep E is retained in position by means of a pin 6 which passes transversely through the extremities of its legs. The hollow spindle is designed in such a manner that its sectional area suffers no reduction at the part where the lateral flats d d are formed for the reception of the U-shaped keep.

The working face of each of the valvedisks is provided with a facing a of incorrosible metal. ing such a facing in position, I form a circular groove (1 in the face of the disk, the inner edge of the said groove terminating in a thin radially projecting lip a The back of the facing is formed with an annular projection a adapted to fit the said groove a and terminates in a centrally projecting rib a located immediately behind the thin lip a of the disk. The facing a having been placed in position, the thin lip a on the disk is, with the aid of calking tools, turned down over the rib a on the facing, whereupon the facing a is securely connected together to the disk A.

The co-eflicient of expansion of the incorrosible metal facing is somewhat greater than that of the steel disk. Prior to inserting the annular projection a of the facing in the circular groove of of the disk, I apply to the outer circumference of the former a strip of stout paper or like combustible material. The mounting of the facing in the disk is then proceeded with in the manner described; the presence of the paper strip preventing metal-to-metal contact between the outer circumference of the annular projection a and the outer circumference of the groove a l/Vhen, however, the valve is employed with superheated steam, the paper or like strip is burned away, and the space previously occupied by it is rendered available for differential expansion on the part of the facing ring a.

A stop-valve constructed in the manner hereinbefore described presents the important advantage that the disk A A forming the valve faces are free to rotate about the axis of the ring C whereon they are mounted; it being well known that constant change in the relative positions of working surfaces Patented Apr. 1915. I

For the purpose of secur-- 2. In a stop-valve of the sliding-gate or Copies of this patent may be obtained for five cents each,.by addressing the Washington, D. 0.

shutter type, the combination With a pair of circumferentially grooved valve-disks, of a ring formed orjprovided' at one side of its periphery With snugs adapted to engage in the grooves in the said valve-disks, and at the other side with a head adapted to engage With a non-rotatable operating spindle formed at its inner extremity With snugs adapted to engage. in the grooves on the valve-disks.

JOHN DEWRANCE. Witnesses WILLIAM W. CADMAR, -FRED HALESTRAP.

Commissioner of Patents, 

